Spam, an electronic version of junk mail, is unsolicited email on the Internet. A filter, on the other hand, is a piece of software that is capable of identifying an email message as spam and blocking or redirecting delivery of a spam message. Some existing methods for generating spam filters rely on collecting spam email messages, processing the messages, and creating filtering rules to be later used to detect spam email. An ability to develop effective filters may be affected by the quantity and quality of spam messages that are available for processing. It is therefore desirable to identify methods that produce increased amount of spam messages that can be used in creating anti-spam filters.